Healy emerged as one of Oakland's many young power-hitting threats last season. He hit .271/.302/.451 with 25 home runs and 78 RBI in 605 plate appearances, the 25-year-old's first full season as an every-day player.

The A's were one of baseball's best home-run hitting teams in 2017, as their 234 total dingers were the fourth-most in baseball. Healy became expendable with the emergence of first baseman Matt Olson and third baseman Matt Chapman, as well as the expectation that Khris Davis will be the team's designated hitter role full-time in 2018.

In return, the A's received Pagan, who should slot into their bullpen as a late-inning relief pitcher. The 26-year-old had a fine rookie season for Seattle, going 3-4 with a 3.22 ERA and a 3.28 fielding independent pitching (FIP) in 34 appearances (50.1 innings). He also posted a 28.6% strikeout rate with a 4.1% walk rate while holding opposing hitters to a .209 batting average.

As for Campos, he's a 17-year-old shortstop who hit .290/.413/.367 in 59 games in rookie ball as part of Oakland's farm system.

Healy should help the Mariners' power output in 2018, as Seattle's 200 team bombs ranked 17th in baseball, while their .424 slugging percentage as a unit was tied for 18th. What he hasn't yet brought to the table, though, is the ability to get on base at a high clip.

The young slugger drew a free pass in a mere 3.8% of his plate appearances last season, the fifth-lowest rate among qualified hitters, while his 23.5% strikeout rate was one of the highest among this group. If we take measure his 100 wRC+ against other qualified first basemen, he ranked 24th out of 28 players, while his 0.2 fWAR was tied for 25th.

We saw a record number of homers hit in 2017, so 25 homers from a player isn't as valuable as it used to be. In fact, Healy was one of 21 first basemen to hit that many homers, and one of 74 big leaguers overall. The change in scenery may have a negative impact on his power numbers, too.

Of Healy's 25 dingers, 14 came at O.co Coliseum, which ranked 11th in home-run factor last season. Safeco Field, his new home for the foreseeable future, ranked all the way down at 20th overall.

Despite his shortcomings, Healy should help improve Seattle at first base, which was a problem spot last year. The players who manned that spot on the diamond combined to hit .245/.313/.396 with 22 homers and a -0.7 fWAR. And on the other end of the deal, Pagan should give Oakland a late-inning arm they desperately needed, as well.